Bump paho-mqtt from 1.6.1 to 2.0.0

Bumps [paho-mqtt](https://github.com/eclipse/paho.mqtt.python) from 1.6.1 to 2.0.0.
- [Release notes](https://github.com/eclipse/paho.mqtt.python/releases)
- [Changelog](https://github.com/eclipse/paho.mqtt.python/blob/master/ChangeLog.txt)
- [Commits](eclipse-paho/paho.mqtt.python@v1.6.1...v2.0.0)

---
updated-dependencies:
- dependency-name: paho-mqtt
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

setup.py

@@ -68,7 +68,7 @@ def package_vars(version_file):
     py_modules=[splitext(basename(path))[0] for path in glob("src/*.py")],
     install_requires=[
         "configobj == 5.0.8",
-        "paho-mqtt == 1.6.1",
+        "paho-mqtt == 2.0.0",
         "pyserial == 3.5",
         "pyusb == 1.2.1",
         "semver == 3.0.2",